This disclosure is directed to systems and methods using digital signal processing techniques to improve Image Quality (IQ), and/or to modify IQ according to a user's desires or requirements, of an image produced in an image forming device.
IQ for images formed in an image forming device is dependent on a number of complex and varyingly related factors. Principal among these factors is that an output IQ may depend on an ability to accurately reproduce images in accordance with the Tone Reproduction Curve (TRC) for a specific image forming device. It should be appreciated that TRCs involve a measure of the scanning response, the image processing, and the image output terminal (IOT) response for the image forming device. In general, the scanning response for a specific image forming device tends to be very stable. Also, image processing, though capable of being manipulated, tends to be very stable. However, IOT response can deviate during xerographic optimization for a specific device, and will tend to vary across different devices within a family and different families of devices. IOT response may also vary with environmental conditions and with an aging of one or more components of the image forming device. An outcome of all of this is that regardless the inclusion of carefully controlled TRCs across a family of image forming devices, IQ will vary from a typically performing machine.
Conventionally, IQ across a family of machines is reviewed and a center line machine is identified as a typically performing machine and the IQ is optimized on this machine, once the system is stable. Later, any change in IOT response will require that an image processing TRC be compensated by being re-optimized. This process conventionally requires a new version of system software into which the optimization is built. Development and delivery of optimization-adjusted TRCs can prove a significant disadvantage. The process is time consuming, can be expensive, and may be difficult to implement at individual customer or end-user sites. The alternative, however, is that failing to resolve for migration in IOT response over time will result in reduced IQ for the images formed in individual image forming devices.